The present invention relates to a protective cover detachably installed on a cutting machine/engraving machine combination, and more particularly to a protective cover which can be quickly, safely and conveniently installed and taken off from the main body according to the using state of the combination.
FIG. 6 shows a conventional cutting machine having a main body 8 in which a pneumatic motor (not shown) is installed. A rotary shaft 82 of the motor is coupled with a sand disk 83 for cutting off a work piece. The front end of the main body 8 is disposed with a thread section 84. A nut 85 is screwed on the thread section 84 to tighten a protective cover 86 which partially covers the sand disk 83. When cutting a work piece, the sand disk 83 may be broken and sparks will be produced so that the protective cover serves to protective a user from being hurt by the broken sand disk and prevent the sparks from affecting the sight of the user or burning the user. Therefore, it must be ensured that the protective cover is truly fixed without loosening. Otherwise, the safety in use of the cutting machine can be hardly ensured. When the sand disk 83 is replaced by a grinding stone 91 and relevant components, the cutting machine is changed into an engraving machine (as shown in FIG. 7). However, when using the engraving machine, the protective cover 86 is unnecessary and is changed into a flat cover 92 so that the protective cover must be detached and removed. At this time, a user must untighten the nut 85 with a large wrench. Such operation is quite inconvenient for the user. Moreover, when untightening or tightening the nut 85, due to the obstruction of the protective cover 86 (the protective cover 86 has small openings on two sides), each time the wrench can untighten or tighten the nut by a small angle so that such procedure is quite troublesome and time-consuming.
It is therefore a primary object of the present invention to provide a protective cover detachably installed on a cutting machine/engraving machine combination. The protective cover is disposed with a fixing ring which can be directly tightened on an outer thread section of the main body. The gap of the split of the fixing ring can be changed by means of a tightening member so as to tightly engage the inner thread section of the fixing ring with the outer thread section of the main body without loosening. Therefore, the protective cover can be quickly and conveniently installed and taken off from the main body.
According to the above object, the combination includes:
a tubular main body, a motor being disposed in the main body, a switch being disposed on an outer side of the main body to control the rotation of the motor, the motor having a rotary shaft axially forward protruding out of the main body, a front end of the rotary shaft being fixed with a sand disk or a grinding stone, an outer thread section being disposed at the front end of the main body, the outer thread section can be alternatively fixed with a flat cover or a protective cover; and
a protective cover disposed at the front end of the main body to cover one half of the sand disk, a rear end of the protective cover having a fixing ring disposed on the outer thread section of the main body, the inner wall of the fixing ring is formed with an inner thread section cooperating with the outer thread section of the main body, the fixing ring being formed with a split, the fixing ring being disposed with a tightening member on two sides of the split. By means of tightening or untightening the tightening member, the gap of the split can be changed so as to tighten the fixing ring on the outer thread section of the main body.
The present invention can be best understood through the following description and accompanying drawings wherein: